<h2>DESCRIPTION</h2>

<em>i.in.spotvgt</em> imports SPOT Vegetation (1km, global) NDVI data sets.
After import the digital numbers (DN) are remapped to VEGETATION NDVI
values and the NDVI color table is applied. The imported DN map is 
removed after remapping.
<p>Apparently missing raster cells due to bad pixel quality are reconstructed
by the SPOT operating team in the NDVI file. The differences between the
filtered (-a flag) and raw NDVI map should be compared.

<h2>NOTES</h2>

The SPOT VGT files are delivered in HDF4 (Hierarchical Data Format Release 4)
format. It is required to have the GDAL libraries installed with HDF4 support.

<h3>Export of entire world SPOT VGT maps</h3>

When working with SPOT VGT with entire world extent, it is recommended
to zoom to <i>w=180W</i> and <i>e=180E</i> instead of using the map
extent for map export. These entire world SPOT VGT data are exceeding
-180.0 degree which can lead to unhelpful large East-West coordinates in
the exported file. It is also recommended to then use an export command
which respects the user settings. Example:

<div class="code"><pre>
# import:
i.in.spotvgt 0001_NDV.HDF

# export:
g.region w=180W e=180E n=75:00:16.071429N s=56:00:16.069919S res=0:00:32.142857 -p
r.out.gdal 0001_NDV format=GTiff out=spotndvi.tif
</pre></div>

<h2>SEE ALSO</h2>

<em>
<a href="r.in.gdal.html">r.in.gdal</a>,
<a href="r.out.gdal.html">r.out.gdal</a>
</em>

<h2>REFERENCES</h2>

<a href="http://free.vgt.vito.be/">SPOT Vegetation (1km, global) NDVI data set server</a><br>
<a href="http://www.vgt.vito.be/faqnew/index.html">SPOT Vegetation FAQ</a><br>
<a href="http://www.vgt.vito.be/faqnew/">1.13 How must I read the 8 bits of the status map?</a> - Quality map

<h2>AUTHOR</h2>

Markus Neteler

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